Which statement is true?
a) all waves travel at the same speed through any medium.
b) all waves travel at the same speed if no medium is present.
c) electromagnetic waves require a medium, but mechanical waves do not.
d) mechanical waves require a medium, but electromagnetic waves do not.

Boris needs to buy plastic spoons. brand a has a box 42 spoons for $2.37. brand b has a box of 72 spoons for $3.57. find the unit price for each brand. then state which brand is the better buy based on the unit price. round your answer to the nearest cent.

Joe has some money in his bank account he deposits 45$ write an expression that represents the amount of money in joe's account

Formulate the indicated conclusion in nontechnical terms. be sure to address the original claim. the foundation chair for a hospital claims that the mean number of filled overnight beds is over 523, and she is therefore justified starting a funding campaign to add a wing to the hospital. assuming that a hypothesis test has been conducted and that the conclusion is failure to reject the null hypothesis, state the conclusion in nontechnical terms.